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There are many possible symptoms of lead poisoning. Lead can affect many different parts of the body. Over time, even low levels of lead exposure can harm a child's mental development. The possible health problems get worse as the level of lead in the blood gets higher. Possible complications include:

Reduced IQ
Slowed body growth
Hearing problems
Behavior or attention problems
Failure at school
Kidney damage
The symptoms of lead poisoning may include:

Irritability
Aggressive behavior
Low appetite and energy
Difficulty sleeping
Headaches
Reduced sensations
Loss of previous developmental skills (in young children)
Anemia
Constipation
Abdominal pain and cramping (usually the first sign of a high, toxic dose of lead poison)
Very high levels may cause vomiting, staggering gait, muscle weakness, seizures, or coma